Computing and communication networks typically include devices, such as routers, switches or gateways, which transfer or switch data, such as packets, from one or more sources to one or more destinations. A network switch or router, in particular, may include a networking device that connects network segments and computing devices.
The size and capacity of a particular router may vary considerably depending on the intended application of the router. For example, routers may provide connectivity inside enterprises, between enterprises and the Internet, and inside Internet Service Providers (ISPs). The largest routers may interconnect ISPs, may be used inside ISPs, may be used inside large data center networks, or may be used in very large enterprise networks. The smallest routers may provide connectivity for small businesses and home offices.
Large routers, such as those marketed to ISPs, may be distributed as a modular “chassis,” which the ISP may purchase and connect together to form a single large, high capacity router. It may be desirable for the manufacturer of such large routers to test the different modular portions before delivery to the customer. Additionally, during operation, routers may sometimes fail. To minimize cost and testing time during manufacture or in response to operational failure of the router, it may be particularly desirable to test the modular portions of the router without the modular portions connected as a complete router. For example, a switch fabric chassis may need to be tested during manufacture or in response to operational failure. The switch fabric chassis, however, may be a protocol free device that does not include, for example, logic capable of implementing Internet Protocol (IP) routing. Accordingly, existing Transmission Control Protocol (TCP)/IP diagnostic tests cannot be run through the switch fabric chassis.